Var.: Сверху ясно, снизу грязно Cf: An angel on top but a devil underneath (Am.). Beauty may have fair leaves, but (yet) bitter fruit (Br.). A clean glove often hides a dirty hand (Am.). A fair face, a false heart (Br.). A fair face may hide a foul heart (Am., Br.). Fair without and false within (Br.). Foppish dressing tells the world the outside is the best of the puppet (Br.). Many a rosy apple is rotten to the core (Am.). The reddest apple may have a worm in it (Am.). There is many a fair thing full false (Br.)
Русско-английский словарь пословиц и поговорок. Академик.ру. 2013.